He is a fan character.
Kibble likes superheroes of any kind, which explains his strange accessories. His bucket might be meant to be a helmet, while the rubber band might be meant to be his belt.
In his daily life, Kibble is very socialized. He enjoys doing various activites like bug catching, traveling with others, having a party, and many more. When it comes to welcoming the incoming guests to his house, Kibble cleans up his house before his guest shows up. Despite this, Kibble is actually very ignorant about cleanliness. He cleans his house just to make his friends happy and to avoid any incoming insults. When he's outside, he'll always end up throwing rubbish into random places.
Kibble, despite living alone, has two bedrooms. One is just a regular bedroom, while the other one is filled with Splendid-related or superhero-related merchandise.
Kibble's deaths mostly involve getting crushed or forced into his own bucket.